In order to transfer data between computer systems rapidly and reliably, electro-optic data transmission is increasingly being used as the method of choice. Optical fibers provide resistance to electromagnetic interference, increased security, and increased speed due to a wide potential band width. Optical fibers transmit data from an electro-optical transducer, such as a laser or Light Emitting Diode (LED) to an electro-optical receiver that generates electrical information based upon the signal received. An optical fiber includes a core region that is coated by an annular clad. The core region has an index of refraction greater than that of the clad, so that light is transmitted through the core by total internal refraction. The optical fibers are typically either threaded onto the electro-optical components or latched by the use of connectors such "SC" connectors.
State of the art optical links operate at over 1000 Mbits/second that generates very high electro-magnetic emissions in the range of 100 MHZ-5 GHz. FCC regulations constrain the field strength of radiated emission from certain unintentional radiators such as personal computers, CPU boards, power supplies, and peripherals. FCC regulations provide that the radiated emission from such unintentional radiators at a distance of three meters shall not exceed the following values:
Frequency of emmision Field Strength MHZ (micro volts/meter) 30-88 100 88-216 150 216-960 200 Above 960 500
In order to limit such emissions, external shielding has been used around the electro-optical component of such optical links. These shields provide an opening that allows threaded or "SC" type connectors to attach to the electro-optical components. Since these connectors are typically plastic they do not serve as a shield to emissions. This electromagnetic "hole" in the shield allows electromagnetic inference to escape the shielded area and may cause the equipment to exceed the maximum values provided for radiated emissions as specified by the FCC.
Consequently, a significant need continues to exist in the art for a shield that will block electro-magnetic interference from escaping from the shielded area. Specifically, a significant need continues to exist for a cost effective shield that blocks significant amounts of the emissions yet allows quick, easy and reliable connection to the electro-optic component.